Automotive news, tips and more

Monthly Archives: March 2017

You should be very concerned, because an overheated engine can be far more than an inconvenience. In extreme cases, driving an overheated engine even a short distance can destroy the cylinder head, engine block or internal parts.

Fortunately, most modern vehicles have a gauge that displays a constant temperature reading of the coolant circulating inside the engine, giving the driver an early warning about the cooling system.

The normal operating temperature for most engines is in a range of 195 to 220 degrees Fahrenheit, though most dashboard temperature gauges don’t show an exact temperature. Instead, there are typically markings for cold and hot on the edges of the gauge and a normal range in the middle. In most vehicles, the temperature needle will be at or near the center when the engine is at normal operating temperature, which usually takes at least a minute or two to reach after starting a cold engine.

In some vehicles, the needle may never reach the middle of the gauge, so don’t be alarmed if it stops short of the midpoint. Instead, you should monitor where it is when the engine is fully warm so that you know what “normal” is for your engine. That way, if the needle starts creeping up higher, closer to the hot mark, you’ll have early notice that something is wrong in the cooling system.

Using the air conditioning at full blast, stop-and-go driving on a scorching day, and towing can raise the engine temperature above normal, so don’t panic if there’s a small change in the gauge reading. You can pull off the road for a while or turn off the A/C and turn on the heater to try to cool things off.

If the temperature gauge consistently shows the engine is warmer than normal, have your cooling system checked ASAP.

Today, an increasing number of new vehicles don’t have temperature gauges. Instead, they have a warning light that (usually) glows blue when the engine is cold — one way of telling you that turning on the heater will generate cold or cool air. The blue light goes off once the engine reaches its normal temperature.

All vehicles also have a warning light that’s supposed to come on when the engine exceeds its normal temperature (it also illuminates for a couple of seconds when you start the engine). Without a gauge, though, it’s anybody’s guess as to how high above normal the temperature is or how long it’s been above normal.

The water pump, often referred to as the coolant pump, circulates liquid coolant through the radiator and engine cooling system, and is powered by the engine itself. It ensures that the engine temperature is maintained at a safe level while operating. If it fails, the engine may overheat, causing serious damage if left unchecked.

How do I know it’s time to replace my water pump?
A pump that leaks even a little is on its last legs, and one that makes rumbling or screeching noises is getting close to failing. Another sign that it’s about time to replace the pump is when the engine temperature warning light is illuminated on the dash. Contaminated coolant and corrosion can cause seals and internal pump parts to fail.

Why do I need to change my water pump?
Water pumps generally don’t need to be replaced unless leaks develop or the pump completely fails. An important exception to this is that some water pumps are driven by the timing belt, and not the accessory drive belt, and most mechanics recommend the pump be replaced at the same time as that belt (and vice versa). That’s because both are hard to reach and require considerable time and labor cost to replace.

How often should I replace my water pump?
With any luck, you shouldn’t have to replace a water pump even if you keep a vehicle for 10 years or more; they often last that long. Unless you see the warning signs listed above, there’s generally no need to replace it unless you are replacing the belt that drives it.

No, you don’t, according to every auto manufacturer we’ve talked to. The main advocates of the 3,000-mile oil change schedule are those who would profit by it: repair facilities, quick-lube chains and service departments at some new-car dealers.

Years ago it was a good idea to change the oil and filter frequently, but because of advances in engine materials and tighter tolerances, as well as the oil that goes into engines, most manufacturers recommend intervals of 7,500 miles or more.

Ford, Volkswagen and Porsche, for example, recommend oil changes every 10,000 miles. So does Toyota on several engines, including the Prius’ 1.8-liter four-cylinder and the Camry’s 2.5-liter four-cylinder. BMW says owners can go up to 15,000 miles between oil changes (with synthetic oil).

The intervals vary by manufacturer and engines, so consult your owner’s manual or maintenance schedule to see how often to change the oil in your vehicle and what type of oil to use. You may be surprised. We were surprised to learn that the Camry’s 2.5-liter engine requires 0W20 synthetic oil, for instance.

Manufacturers suggest you change oil more often for “severe” driving conditions, such as frequent trailer towing, extensive stop-go driving or idling in traffic, driving in extreme heat or cold, or frequent short-distance driving in which the engine doesn’t reach full operating temperature.

Some car companies, Ford and General Motors among them, equip most vehicles with oil life monitors that tell you when it’s time to change the oil based on vehicle speed, engine temperature, climate conditions, number of cold starts and other factors. They can all cite examples from owners who say the oil-life monitors indicated they could go even longer than the recommended change intervals.

If you’re nervous about going 10,000 miles or more between oil changes, then do it every six months, when you probably should also have your tires rotated (also explained in your owner’s manual). GM says to change your oil at least once a year even if the service indicator warning light doesn’t come on. With longer recommended intervals between oil changes, it’s more important to check the oil level at least once a month to make sure you have enough.

But to change oil every 3,000 miles is probably wasting money. Environmentalists say it also adds to the glut of used oil that must be recycled or disposed, and the state of California is trying to discourage the practice.

Cleaning fuel injectors is a service frequently recommended by dealers and repair shops, but unless there are noticeable signs of clogged injectors (such as a rough idle, stalling, poor acceleration or high emissions levels) it might not be necessary. One tipoff is that fuel injector cleaning is not typically listed on automakers’ routine maintenance schedules.

Many shops promote a quick/easy injector service that runs a cleaning solution through the injectors while they’re still mounted in the engine. A more thorough (and expensive) process for severely clogged injectors requires removing the injectors and cleaning them on a machine designed for that purpose.

Fuel injectors clog when deposits build up over time and thousands of miles; when that happens, they don’t deliver the fine mist of gas that provides maximum performance and efficiency. If that happens, you’ll notice a loss of engine performance or lower fuel economy.

The type of gasoline you use also can be a factor. All gasoline is required to contain detergents that prevent carbon deposits, varnish and other gunk from forming in the fuel system, but not all brands use the same amount. Lower-priced brands often use only the minimum, but the so-called Top Tier brands use more detergents, and some vehicle manufacturers recommend them because of that.

Detergents have been required by the EPA since 1995 because many vehicle owners complained of clogged injectors and fuel-system deposits. Not only has gasoline gotten better since then, but so have the injectors, so problems aren’t as widespread as they used to be.

However, gasoline direct injection, a more sophisticated injection system that operates under higher pressure, is becoming commonplace in engines, and some GDI systems have proved to be more prone to clogging than regular fuel injection.

The fuel pump sends fuel from your car’s gas tank to its engine. Fuel pumps are usually electrically powered and located directly in or on the fuel tank. The ease and cost of replacement depends on the car’s design, and the decision to replace it should be undertaken only after determining that the problems aren’t electrical or related to the fuel lines.

How do I know if my fuel pump is bad?
The most obvious sign is that your car won’t start because fuel isn’t getting to the engine, though there are many possibilities for a no-start situation. One way to tell if the fuel pump is at fault is that when you turn the ignition on you can’t hear the pump motor activate inside the gas tank. Another is intermittent loss of driving power, particularly during acceleration or while driving at highway speeds. If the pump appears to be OK, the problem might be that the fuel pickup in the tank is clogged and can’t deliver enough gas.

How often should I replace my fuel pump?
With luck, the fuel pump will last the life of your vehicle. Fuel pumps are not a regular maintenance item, so they generally are replaced only on an as-needed basis. Some owners replace them before they fail as preventive maintenance, but unless the pump is showing signs of failing, there is little reason to do so. Many vehicles have fuel filters that can clog, so the filter should be checked (and replaced if needed) when diagnosing issues with a fuel pump.

Why do I have to replace my Fuel pump?
If the pump is showing signs that it may fail it should be replaced – the vehicle won’t start or intermittently loses power — or you may find yourself stranded.

Most vehicles have a rubber belt on the front of the engine that drives accessories such as the air-conditioning compressor, power steering pump and alternator. If this accessory drive belt (also called a V or serpentine belt) breaks, the battery won’t get charged, the air conditioner won’t blow cold air and the power steering will go out. In addition, if the belt drives the water pump, the engine could overheat.

Most manufacturers call for periodic inspection of the belt as part of scheduled maintenance, but few list a specific replacement interval, and inspection intervals vary widely.

Mercedes-Benz, for example, says to inspect the belt every two years or 20,000 miles, while Volkswagen says to check it every 40,000 miles. On most Ford vehicles, the manufacturer says to start inspecting it after 100,000 miles and then every 10,000 miles. On many GM vehicles, the first recommended inspection is at 150,000 miles or 10 years.

Though these belts often last many years, they can become cracked or frayed and need to be replaced. That’s why they should be inspected at least annually on vehicles that are more than a few years old. In addition, if a belt needs to be replaced, the pulleys and tensioners that guide the belt should be inspected to determine if they caused damage other than normal wear.

A belt that isn’t cracked or frayed may look like it’s in good shape, but grooves on the hidden side may be worn enough that the belt slips on the pulleys that drive the accessories. That will cause problems in systems that rely on the belt to keep things humming. For example, a slipping drive belt may cause the alternator to work intermittently or at reduced power, and the battery won’t get fully recharged as a result, perhaps triggering a warning light.

Another sign of a worn belt is a squealing noise under acceleration. That could indicate that the belt is slipping because of wear, a belt tensioner is loose or a pulley is out of alignment.